[win/asan] GetInstructionSize: Remove duplicate instruction FF 25 ....

[bernhardu]

It appears already some lines above with this comment:
"Cannot overwrite control-instruction. Return 0 to indicate failure.".

Replacing just the comment in the first appearance.

Found after creating the test in #113085.

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[llvmbot]

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: None (bernhardu)

Changes

It appears already some lines above with this comment:
"Cannot overwrite control-instruction. Return 0 to indicate failure.".

Replacing just the comment in the first appearance.

Found after creating the test in #113085.

---

Full diff: https://github.com/llvm/llvm-project/pull/116894.diff

1 Files Affected:

• (modified) compiler-rt/lib/interception/interception_win.cpp (+1-2)

diff --git a/compiler-rt/lib/interception/interception_win.cpp b/compiler-rt/lib/interception/interception_win.cpp
index cfd92619a1e15d..fa2b769bcb8752 100644
--- a/compiler-rt/lib/interception/interception_win.cpp
+++ b/compiler-rt/lib/interception/interception_win.cpp
@@ -631,7 +631,7 @@ static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {
       return 2;
 
     // Cannot overwrite control-instruction. Return 0 to indicate failure.
-    case 0x25FF:  // FF 25 XX XX XX XX : jmp [XXXXXXXX]
+    case 0x25FF:  // FF 25 XX YY ZZ WW : jmp dword ptr ds:[WWZZYYXX]
       return 0;
   }
 
@@ -864,7 +864,6 @@ static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {
     case 0x75FF:  // FF 75 XX : push dword ptr [ebp + XX]
       return 3;
     case 0xC1F7:  // F7 C1 XX YY ZZ WW : test ecx, WWZZYYXX
-    case 0x25FF:  // FF 25 XX YY ZZ WW : jmp dword ptr ds:[WWZZYYXX]
       return 6;
     case 0x3D83:  // 83 3D XX YY ZZ WW TT : cmp TT, WWZZYYXX
       return 7;

[zmodem]

lgtm

[bernhardu]

ping

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